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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

27029 results found.

  1. GRB 080408A: GAO 150cm telescope Optical Observation
  2. GRB 090422: Liverpool Telescope observations
  3. GRB 090418B: Suzaku WAM observation of the prompt emission
  4. GRB 090422: Swift detection of a burst
  5. GRB 090418C: Fermi GBM Detection
  6. Swift-BAT trigger 349718 is not a burst
  7. GRB 090419: Swift/UVOT Observations
  8. GRB 090418A: Swift/UVOT Observations
  9. GRB 090417B: Swift/UVOT Upper Limits
  10. GRB 090419: Swift-XRT refined analysis
  11. GRB 090419: GROND detection of afterglow candidate
  12. GRB 090419: Swift-BAT refined analysis
  13. GRB 090418: Swift XRT refined analysis
  14. GRB 090418A: ROTSE-III Refined Analysis
  15. GRB 090419: Swift detection of a burst
  16. GRB 090418: Swift-BAT refined analysis
  17. GRB 090417B: Swift-XRT refined analysis
  18. GRB 090417B: Swift-BAT further refined analysis
  19. GRB 090418: PAIRITEL NIR detection
  20. GRB 090418 Lick Redshift
  21. GRB 090418: ROTSE-III Confirmation of Optical Counterpart
  22. GRB 090418: Swift detection of a burst with optical afterglow
  23. GRB 090411B: Suzaku WAM observation of the prompt emission
  24. GRB 090411A: Suzaku WAM observation of the prompt emission
  25. GRB 090417B: Swift-BAT refined analysis
  26. GRB 090417A: Swift-BAT refined analysis
  27. GRB 090417B: Swift detection of a burst
  28. GRB 090417: Swift detection of a short burst
  29. GRB 090412: Fermi GBM detection
  30. GRB 090411B: Fermi GBM detection
  31. GRB 090411A: Fermi GBM detection
  32. GRB 090410: Suzaku WAM observation of the prompt emission
  33. Fermi GBM trigger 261106787 is not a GRB
  34. GRB 090410: Swift-BAT refined analysis
  35. GRB 090410: Swift detection of a burst
  36. GRB 090409: Fermi GBM detection
  37. Swift-BAT Trigger 348781 is not a GRB
  38. Swift-BAT Trigger 348720 is not a GRB
  39. GRB090408, RIMOTS optical upper limits
  40. GRB 090408: Xinglong TNT optical Upper Limit
  41. Swift-BAT trigger 348781: almost certainly not a burst
  42. Fermi GBM Detection of a weak source
  43. GRB 090408B: MASTER II-Kourovka optical observations
  44. GRB 090408: Swift detection of a burst
  45. GRB 090407: Swift-XRT refined analysis
  46. GRB 090407: Swift UVOT Upper Limits
  47. GRB 090407: Swift-BAT refined analysis
  48. GRB 090407: ROTSE-III Optical Limits
  49. GRB 090407: Swift detection of a burst
  50. GRB 090405: Fermi GBM Detection
  51. GRB 090403: Fermi GBM detection
  52. Swift/UVOT observations of GRB090404
  53. GRB 090404: optical observations at BOOTES-3 and 1.5-m OSN
  54. GRB 090404: Swift-XRT Team refined analysis
  55. GRB 090404: Xinglong TNT optical Upper Limit
  56. GRB 090404: Swift-BAT refined analysis
  57. Fermi Gamma-ray Burst Monitor trigger 260428446 is not a GRB
  58. GRB 090404: Swift detection of a burst
  59. GRB 090401A: Suzaku WAM observation of the prompt emission
  60. GRB 090401B: Suzaku WAM observation of the prompt emission
  61. Konus-Wind observation of GRB 090401B
  62. GRB 090401B: Xinglong TNT optical Upper Limit
  63. GRB090401B, RIMOTS optical upper limits
  64. GRB 090328: Fermi-LAT refined analysis
  65. Swift/UVOT observations of GRB090401B
  66. GRB 090401B: AGILE refined analysis
  67. Swift/UVOT observations of GRB090401B
  68. GRB 090401B: Swift XRT Refined Analysis
  69. GRB 090331: Fermi GBM detection
  70. Konus-Wind observation of GRB 090401A
  71. GRB 090401B: Swift-BAT refined analysis
  72. GRB 090401B: Swift detection of a burst
  73. GRB 090401, Swift-BAT refined analysis
  74. GRB 090323: Further TLS detections - a break?
  75. GRB 090401: Swift detection of a burst
  76. GRB 090324: Suzaku WAM observation of the prompt emission
  77. GRB 090326: Fermi GBM detection
  78. GRB 090328B: Fermi GBM Detection
  79. GRB 090330: Fermi GBM detection
  80. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  81. GRB 090328: Swift XRT refined analysis
  82. Konus-Wind observation of GRB 090328
  83. GRB 090328: Swift UVOT observations
  84. Fermi LAT and GBM detections of GRB090328
  85. GRB 090323: TLS detection at 5 days, no break
  86. GRB 090327: Fermi GBM detection
  87. GRB 090323: Lick observations
  88. GRB 090323: Optical observation of xinglong TNT
  89. GRB 090323 TLS detection - still bright
  90. GRB 090323: UVOT Detection of Afterglow
  91. Konus-Wind observation of GRB 090323
  92. GRB 090323 Gemini-South Redshift
  93. GRB 090323: GROND Detection of the Afterglow and Photo-z
  94. SGR J1550-5418: two Fermi GBM triggers on March 22
  95. GRB 090320C: Fermi GBM Detection
  96. Fermi GBM and LAT detections of GRB 090323
  97. GRB 090320B: Fermi GBM detection.
  98. GRB 090319: Fermi GBM detection
  99. GRB 090320A: Fermi GBM detection
  100. GRB 090315: Suzaku WAM observation of the prompt emission

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